1. Field of the Invention
This invention relates to speed sensor switches of the flyweight actuated variety and especially to such switches which use an over centertype action to cause abrupt connection and disconnection of electrical contacts.
2. Description of Related Art
Speed sensitivity switches operated through centrifugal flyweights are often use to provide on/off switching control for motor, solenoid and similar control systems. In order for such a switch to be effective, it must be rugged, reliable and easy to operate.
Among centrifugally operated speed sensor switches suggested in the past is the switch shown in U.S. Pat. No. 985,069, issued Feb. 21, 1911 to Schug, which shows a plurality of flyweights mounted on a rotating shaft. The flyweights are connected to a collar which is urged forwardly upon radial outward movements of the weights. The collar urges a movable contact into engagement with a stationary contact. U.S. Pat. No. 2,846,539, issued Aug. 5, 1958 to Farr, shows a similar speed responsive switch wherein outward movement of flyweights is directly transformed into axial movement of a collar carrying movable contacts. U.S. Pat. No. 2,897,309, issued Jan. 28, 1959 to Randol, shows another speed responsive switch mechanism. The Randol mechanism includes a plurality of flyweights which move radially outward from a rotating shaft against the force of an axial aligned spring to separate the movable and stationary contacts of a switch. U.S. Pat. No. 3,717,733, issued Feb. 20, 1973 to Berezansky, shows a centrifugal switch wherein radial outward movement of a pair of flyweights causes axial movement of a sleeve through a linkage arrangement. The sleeve abuts against and forces movement of a switch arm containing a movable contact, forcing the switch arm to abruptly change position to an over center position and enter into electrical engagement with a stationary contact.